The present invention relates to improved devices, methods, and kits for use in open-wedge osteotomy procedures in which the communication between a wedge member and a plate member allows for compatibility with a wider range of patient anatomies and greater ease of use for implantation.
An osteotomy is a surgical procedure whereby a bone is cut to shorten, lengthen, or change its alignment. It may be performed to correct deformities such as a hallux valgus, a progressive forefoot deformation, or to relieve pain from arthritis, especially in the hip or knee. The procedure usually entails either: the removal of a typically wedge-shaped portion of a bone by cutting perpendicular to the long axis of the bone, whereupon the bone may be “closed,” i.e., fused together at the space and allowed to heal; or a simple partial cut perpendicular to the long axis, whereupon the bone may be “opened” and fixated with an appropriate device. For example, an implant may be inserted into the space, or a bone plate may be affixed to the bone adjacent to the space, to maintain or increase the space. The “closing” or “opening” changes the spatial relationship between the remaining portions of the bone in order to adjust its alignment or length.
Open-wedge osteotomy refers to a specific type of osteotomy procedures in which a partial cut perpendicular to the long axis of the bone is made and opened subsequently. The correction is maintained by using an appropriate fixation device such as, for example, a plate with screws. Additionally, a wedge or bone graft can be added to fill the space that is opened so that the bone may return to a load-bearing state and also to facilitate bone healing. The implanted wedge helps to maintain the opened space by allowing the bone to transmit force to the wedge, thereby preserving the surgeon's aimed reduction or expansion of the angle of the bone. Depending on the location and type of open-wedge osteotomy, an additional fixation plate may also need to be affixed to the bone. A known method for performing the procedure includes performing a partial cut of a bone, subsequently opening the partial cut using a tool (e.g., an osteotome), inserting a wedge into the resultant space of the bone, positioning a bone plate against the wedge, and securing the plate to the bone. Depending on the location and type of osteotomy performed, an additional fixation means (e.g., a plate or staples) may further be implemented.
Current open-wedge osteotomy systems include either: a bone plate integral with a rigid, fixed wedge where the orientation of the wedge relative to the plate is predefined; a wedge that is attached to the implant with a screw; or a bone plate without a wedge. Due to many factors, including natural anatomic variations among patients and the location of an incision made for an osteotomy, a bone plate with an integral wedge is not optimal for all situations. Attaching the wedge to the bone plate with a screw offers some flexibility; however, it also requires yet another component to be implanted in the body. Furthermore, the preferences of practitioners may vary, as some prefer to implant wedge-less bone plates and others prefer to use the plates with a wedge. Therefore, a health care provider may be forced to keep a large inventory of incompatible plate and plate-wedge configurations to ensure proper placement of the bone plate; or, a surgeon might otherwise be relegated to securing the plate in a less-than optimal position.
Thus, there exists a need for improvements in open-wedge osteotomy that provide a greater variety of plate-wedge configurations.